Moody Mercury shows its hidden colours

It might look like poor old Mercury is feeling a bit blue, but fear not - these are false-colour images produced by NASA's Messenger space probe.

To the human eye, the closest planet to the sun is covered in a dull mottling of brown-grey splodges. Filtering the light from its surface lets researchers see chemical, mineralogical and physical differences in the planet's rocks that will help us understand its history and evolution.

In this view, white and light blue streaks show lines of material thrown up and spread across the surface by relatively recent impacts. Deep blue regions are rich in an as-yet unknown mineral, while the orange spots correspond to ancient volcanic plains.